Volume control over shared trunk lines in intercom systems

ABSTRACT

Systems and methods for volume control over intercom trunk lines. One example method includes receiving, from a first keypanel coupled to a first intercom, a call request identifying a remote keypanel coupled to a second intercom. The method includes transmitting a trunk request based on the call request and receiving a trunk setup message. The method includes activating a first crosspoint to provide a two-way audio connection between the first and second intercom devices. The method includes applying a trunk gain value to the first crosspoint based on the remote keypanel and transmitting, with an audio gain based on the trunk gain value, an audio stream received from the first keypanel. The method includes receiving, from the second intercom, a gain adjustment value associated with the first keypanel and the remote keypanel and applying an adjusted trunk gain value to the first crosspoint based on the gain adjustment value.

FIELD

Embodiments described herein relate to intercom systems, intercomdevices, and their methods of operation, and, more particularly, tosystems and methods for volume control over shared trunk lines.

SUMMARY

Intercom systems, for example, broadcast intercom systems, may includelarge numbers of audio ports (typically in the range of 100 to 1000ports). Each port includes an audio input and an audio output.Intelligent devices, such as keypanels, can be connected to each port.Each port can listen to a mix of other sources (ports), atindividually-controlled levels.

Trunking allows audio data to be transported between a port in oneintercom and a port in a different intercom. As an example, this allowsa keypanel user to call a user in a different intercom. The recipienthears the call, and receives a tally (e.g., a flashing key) to indicatewho is calling. The recipient can then reply, allowing for a 2-wayconversation. This is analogous to a telephone trunk line connecting atelephone user connected to the telephone central office (CO) in onecity to a telephone user connected to a CO in another city.

Some broadcast intercoms support “forking,” in which multipleindependent calls can be carried on the same trunk without interference,as long as all of the calls have one port in common at one end. Forexample, a keypanel K1 in intercom X may be connected via trunk T1 tokeypanel K2 in intercom Y. If a keypanel K3 (also in intercom Y) callsK1, that audio can also be carried on the existing trunk T1. Forkingsignificantly reduces the number of trunks required in a system.

Trunks paths are determined dynamically, based on the availableresources. Note that each trunk is a simple bi-directional audio stream,carrying one audio signal (which may be a mix of sources). It is not amultiplexed channel; the audio stream cannot be separated out into itsindividual components.

Keypanel users often monitor multiple audio streams, or participate inmultiple audio conferences over a single keypanel. Accordingly, userswant to be able to control the level at which they hear different audiosources. For example, a user may wish to turn down the volume for asource that they need to monitor in the background, while increasing thevolume for a more urgent conversation. With fixed tie-lines, individualaudio adjustment can be done by adjusting the audio level from thetie-line to the listener. However, with intercom trunking, this does notwork. First, the audio adjustment has to be applied dynamically, basedon where the audio enters the intercom (i.e., which trunk line isselected). Second, if the trunk uses forking, then a local audioadjustment would apply to all the conversations carried over the trunk,whereas the user may want to adjust just one component of theconversation.

Accordingly, systems and methods are provided herein for remote volumecontrol over intercom system trunk lines. Embodiments described hereinallow for, among other things, remote volume adjustments to be appliedpersistently to trunked audio connections between keypanels. Using suchembodiments, users are able to balance the gain for multiple audiostreams received over one or more trunk connections by remotelyadjusting the gain where the audio is patched into its trunk.

One example embodiment provides an intercom device. The device includesa plurality of audio ports including a first port coupled to a firstkeypanel and a second port coupled to a trunk line providing a two-wayaudio connection between the intercom device and a second intercomdevice, a plurality of crosspoints for interconnecting the plurality ofaudio ports, a communication interface, and an electronic processorcoupled to the plurality of crosspoints and the communication interface.The electronic processor is configured to receive, from the firstkeypanel, a call request identifying a remote keypanel coupled to thesecond intercom. The electronic processor is configured to transmit, toa trunk controller via the communication interface, a trunk requestbased on the call request. The electronic processor is configured toreceive, from the trunk controller via the communication interface, atrunk setup message. The electronic processor is configured to activatea first crosspoint of the plurality of crosspoints based on the trunksetup message, the first crosspoint associated with the first port andthe second port. The electronic processor is configured to apply a trunkgain value to the first crosspoint based on the remote keypanel.

Another example embodiment provides a method for remote gain adjustment.The method includes receiving, from a first keypanel coupled to a firstintercom, a call request identifying a remote keypanel coupled to asecond intercom. The method includes transmitting, to a trunkcontroller, a trunk request based on the call request. The methodincludes receiving, from the trunk controller, a trunk setup message.The method includes activating a first crosspoint of a plurality ofcrosspoints based on the trunk setup message, the first crosspointcoupled to a first port associated with a first keypanel and a secondport coupled to a trunk line providing a two-way audio connectionbetween the first intercom device and the second intercom device. Themethod includes applying a trunk gain value to the first crosspointbased on the remote keypanel. The method includes transmitting, with anaudio gain based on the trunk gain value, an audio stream received fromthe first keypanel to the second intercom via the second port. Themethod includes receiving, from the second intercom, a gain adjustmentvalue associated with the first keypanel and the remote keypanel. Themethod includes applying an adjusted trunk gain value to the firstcrosspoint based on the gain adjustment value.

BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS

The accompanying figures, where like reference numerals refer toidentical or functionally similar elements throughout the separateviews, together with the detailed description below, are incorporated inand form part of the specification, and serve to further illustrateembodiments of concepts that include the claimed invention, and explainvarious principles and advantages of those embodiments.

FIG. 1 is a block diagram of an intercom system, in accordance with someembodiments.

FIG. 2 schematically illustrates a trunk controller of the system ofFIG. 1, in accordance with some embodiments.

FIG. 3 schematically illustrates a keypanel of the system of FIG. 1, inaccordance with some embodiments.

FIG. 4 illustrates aspects of the operation of the system of FIG. 1, inaccordance with some embodiments.

FIG. 5 illustrates aspects of the operation of the system of FIG. 1, inaccordance with some embodiments.

FIG. 6 is a flow chart of a method for volume control over sharedtrunked lines, in accordance with some embodiments.

FIG. 7 illustrates an example graphical user interface element, inaccordance with some embodiments.

FIG. 8 illustrates an example graphical user interface element, inaccordance with some embodiments.

Skilled artisans will appreciate that elements in the figures areillustrated for simplicity and clarity and have not necessarily beendrawn to scale. For example, the dimensions of some of the elements inthe figures may be exaggerated relative to other elements to help toimprove understanding of embodiments of the present invention.

The apparatus and method components have been represented whereappropriate by conventional symbols in the drawings, showing only thosespecific details that are pertinent to understanding the embodiments ofthe present invention so as not to obscure the disclosure with detailsthat will be readily apparent to those of ordinary skill in the arthaving the benefit of the description herein.

DETAILED DESCRIPTION

Before any embodiments are explained in detail, it is to be understoodthat the invention is not limited in its application to the details ofconstruction and the arrangement of components set forth in thefollowing description or illustrated in the following drawings. Otherembodiments are possible, and embodiments and examples provide arecapable of being practiced or of being carried out in various ways.

For ease of description, each of the example systems presented hereinare illustrated with a single exemplar of each of its component parts.Some examples may not describe or illustrate all components of thesystems. Other example embodiments may include more or fewer of each ofthe illustrated components, may combine some components, or may includeadditional or alternative components.

FIG. 1 is a block diagram of an example intercom system 100. FIG. 1shows one example of a networked configuration, in which embodiments maybe implemented; other configurations are possible. In the example shown,the system 100 includes a trunk controller 102, a first intercom 104, asecond intercom 106, a trunk editor 108, and an intercom editor 110. Thetrunk controller 102, the first intercom 104, the second intercom 106,the trunk editor 108, and the intercom editor 110 are communicativelycoupled to one another via a communications network 112. Thecommunications network 112 is a communications network includingwireless connections, wired connections, or combinations of both. Thecommunications network 112 may be implemented using a local areanetwork, for example, a Bluetooth™ network or a Wi-Fi network, a widearea network, for example, the Internet, and combinations or derivativesthereof. As would be understood by one skilled in the art, FIG. 1 is asimplified diagram and networks are more complex than the schematicelements depicted in FIG. 1.

The system 100 also includes a first keypanel 114, a second keypanel116, and a third keypanel 118. In some embodiments, one or more of thefirst keypanel 114, the second keypanel 116, and the third keypanel 118may be communicatively coupled to other components of the system 100 viathe communications network 112. It should be understood that the system100 is provided as one example and, in some embodiments, the system 100may include fewer or additional components. In particular, it should beunderstood that although FIG. 1, for ease of description, illustratesonly two intercoms and three keypanels, embodiments of the system 100may include tens, hundreds, or thousands of intercoms and keypanelsinterconnected in various ways.

Each of the first keypanel 114, the second keypanel 116, and the thirdkeypanel 118, described in detail herein with respect to FIG. 3, providea user with two-way audio communications to one or more other users andone-way audio monitoring of one or more audio sources. For example, thedirector in a news studio may use the first keypanel 114 to communicatewith a camera operator, who is using the second keypanel 116. Asdescribed herein, each keypanel has a speaker (which plays the audiocoming from the intercom to which the keypanel is connected) and amicrophone (which sends audio to the same intercom). The keypanel hasvarious keys, which can be used to talk and listen to other users.

To send and receive audio and control signals, a keypanel is connectedto a port on an intercom. For example, as illustrated in FIG. 1, thefirst keypanel 114 and the second keypanel 116 are communicativelycoupled to ports of the first intercom 104 and the third keypanel 118 iscommunicatively coupled to a port of the second intercom 106. Intercoms,for example, the first intercom 104 (described in detail with respect toFIG. 4) include multiple ports for sending and receiving audio and/orcontrol signals. As described herein, audio is routed through anintercom system by interconnecting ports within an intercom atcrosspoints. In each of the first intercom 104 and the second intercom106, one or more ports are audio-only (i.e., there is no keypanelattached). Such ports may be used to bring audio into and out of theintercom (e.g., an audio feed coming from an audio mixing console or anaudio feed to a stage announce speaker).

In some embodiments, each of the first intercom 104 and the secondintercom 106 may be one of the ADAM®, ADAM-M®, or ODIN® intercomsproduced by RTS Intercom Systems®. The first intercom 104 and the secondintercom 106 and configured using the intercom editor 110. In someembodiments, the intercom editor 110 executes AZedit® software productproduced by RTS Intercom Systems' to configure, control, and monitor theoperations of the intercoms and keypanels, in particular, crosspointsand remote volume settings.

As illustrated in FIG. 1, the first keypanel 114 and the second keypanel116 are connected to ports on the first intercom 104, and the thirdkeypanel 118 is connected to a port on the second intercom 106. Asdescribed herein, the trunk controller 102, the first intercom 104, andthe second intercom 106 operate to provide audio communications betweenthe first keypanel 114, the second keypanel 116, and the third keypanel118. For example, as described in detail with respect to FIG. 4, thefirst intercom 104 may establish audio communications between a user ofthe first keypanel 114 and a user of the second keypanel 116, byconnecting their respective ports within the first intercom 104.

To increase an intercom system's capability, multiple intercoms may betied together via trunking. Trunking allows a user in one intercom toaccess resources in another intercom (e.g., to call a keypanel that isconnected to a different intercom). For example, as described in detailwith respect to FIG. 5, the first keypanel 114, the second keypanel 116,or both, may send and receive audio communications to the third keypanel118 via the first intercom 104, the second intercom 106, and one or moreof a plurality of interconnecting trunks 120. A trunk is an audio-onlyconnection from one port in one intercom to another port in a differentintercom. Calls from the first intercom 104 to the second intercom 106(i.e., trunked calls) are managed by the trunk controller 102.

The trunk controller 102, described in detail herein with respect toFIG. 2, operates to configure and select connections between the firstintercom 104 and the second intercom 106. Trunks are predefined (e.g.,using the trunk editor 108). The trunk controller 102 is aware of trunksand what they connect. When a call is placed from one intercom to a userin another intercom, the trunk controller 102 decides which predefinedtrunk to use, and that trunk is then used to pass the audio between thelocal and the remote users (i.e., their respective keypanels). Asdescribed in detail herein, the trunk controller 102 can also sendcontrol messages (e.g., using a suitable communications protocol) to thefirst intercom 104 and the second intercom 106 to adjust gain settingsfor crosspoints within the intercoms. In some embodiments, the trunkeditor 108 executes Trunk Edit® and Trunk Supervisor® software productsproduced by RTS Intercom Systems® to configure, control, and monitor theoperations of the trunk controller 102, in particular, the setup and useof trunks between intercoms and keypanels.

FIG. 2 illustrates an example embodiment of the trunk controller 102 inmore detail. In the example provided, the trunk controller 102 includesan electronic processor 205, a memory 210, a communication interface215, and a display 220. The illustrated components, along with othervarious modules and components (not shown) are coupled to one another byor through one or more control or data buses (e.g., a communication bus250) that enable communication therebetween. The use of control and databuses for the interconnection between and exchange of information amongthe various modules and components would be apparent to a person skilledin the art in view of the description provided herein. In someembodiments, the trunk controller 102 is a network attached computerserver. FIG. 2 illustrates only one example embodiment of the trunkcontroller 102. The trunk controller 102 may include fewer or additionalcomponents and may perform functions other than those explicitlydescribed herein. In some embodiments, the trunk controller 102 is oneof the Trunk Master® family of products (e.g., a model TM-10K®) producedby RTS Intercom Systems®.

The electronic processor 205 obtains and provides information (e.g.,from the memory 210 and/or the communication interface 215), andprocesses the information by executing one or more software instructionsor modules, capable of being stored, for example, in a random accessmemory (“RAM”) area of the memory 210 or a read only memory (“ROM”) ofthe memory 210 or another non-transitory computer readable medium (notshown). The software can include firmware, one or more applications,program data, filters, rules, one or more program modules, and otherexecutable instructions. The electronic processor 205 is configured toretrieve from the memory 210 and execute, among other things, softwarerelated to the control processes and methods described herein.

The memory 210 can include one or more non-transitory computer-readablemedia, and includes a program storage area and a data storage area. Theprogram storage area and the data storage area can include combinationsof different types of memory, as described herein. In the embodimentillustrated, the memory 210 stores, among other things, trunkdefinitions 225 (described in detail herein).

The communication interface 215 is configured to receive input and toprovide system output. The communication interface 215 obtainsinformation and signals from, and provides information and signals to,(e.g., over one or more wired and/or wireless connections) devices bothinternal and external to the trunk controller 102. The communicationinterface 215 may include a wireless transmitter or transceiver forwirelessly communicating over the communications network 112.Alternatively or in addition to a wireless transmitter or transceiver,the communication interface 215 may include a port for receiving acable, such as an Ethernet cable, for communicating over thecommunications network 112 or a dedicated wired connection. It should beunderstood that, in some embodiments, the trunk controller 102communicates with other devices through one or more intermediarydevices, such as routers, gateways, relays, and the like.

The display 220 is a suitable display such as, for example, a liquidcrystal display (LCD) touch screen, or an organic light-emitting diode(OLED) touch screen. In some embodiments, the trunk controller 102implements a graphical user interface (GUI) (e.g., generated by theelectronic processor 205, from instructions and data stored in thememory 210, and presented on the display 220), that enables a user tointeract with the trunk controller 102. In some embodiments, the trunkcontroller 102 enables display remotely, for example, using a display ofthe trunk editor 108 or a display of another remote computer terminal(not shown) via one or more intervening networks.

In some embodiments, the trunk editor 108 and the intercom editor 110are or include computer servers, which include similar components andoverall are constructed and configured similarly to the trunk controller102.

FIG. 3 illustrates one example construction of the first keypanel 114.In the example illustrated, the first keypanel 114 includes a pluralityof electrical and electronic components that provide power, operationalcontrol, and protection to the components and modules within the firstkeypanel 114. The first keypanel 114 includes an electronic controller305, which further includes an electronic processor 310 (e.g., aprogrammable electronic microprocessor, microcontroller, or similardevice) and a memory 315 (e.g., non-transitory, machine-readablememory). The electronic processor 310 is communicatively coupled to thememory 315 and executes instructions stored on the memory 315. Theelectronic processor 310 is configured to retrieve from memory 315 andexecute, among other things, instructions related to the controlprocesses and methods described herein. In other embodiments, the firstkeypanel 114 may include fewer or additional components and may performfunctions other than those explicitly described herein. In someembodiments, the first keypanel 114 is one of the KP-Series® family ofintercom keypanels (e.g., a model KP-5032®) produced by RTS IntercomSystems®.

In the illustrated embodiment, the first keypanel 114 also includes ahuman machine interface 317. The human machine interface 317 includes amicrophone 320, a speaker 325, a display 330, and an input mechanism335. The microphone 320 and the speaker 325 may be constructed invarious configurations. For example, the speaker 325 and the microphone320 may be integrated into a single headset or may be separatestand-alone components. The speaker 325, the microphone 320, the display330, and the input mechanism 335 are electrically coupled with thecontroller 305 and provide input and output functionality for a user ofthe first keypanel 114. In some embodiments, the first keypanel 114generates an audio stream (e.g., a voice message) from the microphone320. In other embodiments, an audio stream may be generated by othersources and received by the first keypanel 114. An audio stream may alsobe stored in the memory 315. User-selectable entries from the inputmechanism 335 selects and directs transmission and reception of audiostreams for the first keypanel 114 as described below.

The input mechanism 335 may have multiple inputs including multiplebuttons, switches, toggles, and the like. Each of these inputs mayactivate communication with one or more particular intercom devices.When one of the inputs of the input mechanism 335 is activated (e.g., bydepressing, toggling, holding, and the like), the controller 305 selectsa particular intercom device selected by the activated input forcommunication, and may send addressing information associated with theselected intercom device to the first intercom 104. The first intercom104 may then activate a communication link between the first keypanel114 and the selected intercom device. The first keypanel 114 may bepreconfigured with an address of each particular intercom device that isassociated with each particular input.

In some embodiments, the second keypanel 116 and the third keypanel 118include similar components and overall are constructed and configuredsimilarly to the first keypanel 114. In some embodiments, the secondkeypanel 116, the third keypanel 118, or both are substantiallyidentical to the first keypanel 114.

As noted, the first intercom 104 is configured to provide audiocommunications between the first keypanel 114 and the second keypanel116. As illustrated in FIG. 4, the first intercom 104 includes aplurality of audio ports 402 (each including an input and an output).The audio ports 402 are configured to create a switching fabric 404. Theswitching fabric 404 may be implemented physically (e.g., using solidstate circuitry) or digitally. Regardless of its construction, theswitching fabric 404 provides crosspoints (including crosspoints405-408) for interconnecting audio inputs and outputs to provide, amongother things, audio connections between keypanels. The first intercom104 includes an electronic controller 410 (e.g., including at least anelectronic processor, a memory, and a communication interface) tocontrol the switching fabric 404 to activate and deactivate thecrosspoints. For example, the electronic controller 410 connects theaudio input of port 2 to the audio output of port 6 at crosspoint 405and the audio input of port 6 to the audio output of port 2 atcrosspoint 408 to provide a connection between the first keypanel 114and the second keypanel 116. In this way, audio originating with themicrophone 425 of the second keypanel 116 is routed to the speaker 320of the first keypanel 114. Likewise, audio originating with themicrophone 325 of the first keypanel 114 is routed to the speaker 420 ofthe second keypanel 116. The electronic controller 410, controls thegain for each crosspoint. The default gain for each crosspoint is 0 dB.

A keypanel may listen to a mix of different audio inputs, similar to anaudio mixing console. For example, as illustrated in FIG. 4, the secondkeypanel 116, in addition to receiving audio from the first keypanel114, also receives audio from input ports 4 and 5, which are patchedinto output port 6 at crosspoints 406 and 407, respectively. Output port6 therefore carries a mix of three audio signals to the speaker 420 ofthe second keypanel 116. Because each crosspoint has its own gain, theuser of the second keypanel 116 can adjust (e.g., using the inputmechanism 335) the relative loudness of the inputs.

FIG. 4 illustrates two keypanels in communication via a single intercom.However, as noted, some intercom systems utilize trunking to provideaudio connections across multiple intercoms. For example, as illustratedin FIG. 5, the first keypanel 114, the second keypanel 116, and thethird keypanel 118 communicate via the first intercom 104 and the secondintercom 106. The second intercom 106 is configured similarly to thefirst intercom 104, and includes a plurality of audio ports 502,configured to create a switching fabric 504, which is controlled by theelectronic controller 506. The first intercom 104 is connected to thesecond intercom 106 via a trunk 508 (one of the plurality ofinterconnecting trunks 120). The trunk may be a physical connection(e.g., a wired connection) or a virtual connection (e.g., using aninternet protocol connection).

When a user of the first keypanel 114 inputs a request to call a user ofthe third keypanel 118, the electronic controller 410 sends a request tothe trunk controller 102 to establish the connections. In response, thetrunk controller 102 sends messages to the first intercom 104 and thesecond intercom 106 to set up the audio via the trunk 508, and to givethe second keypanel 116 an indication that there is an incoming callfrom the first keypanel 114. In response to receiving the messages, theelectronic controller 410 of the first intercom 104 activates crosspoint510 to patch input port 1 to output port 2 (the trunk port) and theelectronic processor 506 of the second intercom 106 activates crosspoint512 to patch input port 4 (the trunk port) to output port 3. In thisway, audio inputs received from the microphone 325 of the first keypanel114 are routed to the speaker 520 of the third keypanel 118. Although,for ease of description, only one-way audio connections are show, itshould be noted that the audio connections may be bi-directional.

In some instances, more than one keypanel may wish to connect to aremote keypanel on another intercom. In such instances, the trunkcontroller 102 will utilize forking to connect multiple users via asingle trunk, thereby reducing the number of required trunks in asystem. For example, as illustrated in FIG. 5, if the second keypanel116 requests a call to the third keypanel 118, the trunk controller 102will instruct the first intercom 104 and the second intercom 106 toestablish that connection via the existing trunk 508. In response, theelectronic controller 410 of the first intercom 104 will activate thecrosspoint 514 to patch input port 5 to output port 2 (the trunk port).When this is completed, the speaker 520 of the third keypanel 118 willnow receive audio from the microphone 325 of the first keypanel 114mixed with audio from the microphone 425 of the second keypanel 116,over the trunk 508.

In some configurations, a keypanel may receive one or more remote audiosources on a trunk line (e.g., as described herein with respect to FIG.5). Because adjusting the gain in the local intercom for the trunk lineadjusts the gain for all audio sourced received on the trunk line, it isnot possible to balance the volume for the mixed audio signals.Therefore, the gain for the individual audio sources must be adjusted attheir respective input crosspoints. Accordingly, FIG. 6 illustrates anexample method 600 for remote volume control over shared trunk lines.Although the method 600 is described in conjunction with the system 100as described herein, the method 600 could be used with other systems anddevices. In addition, the method 600 may be modified or performeddifferently than the specific example provided.

As an example, the method 600 is described as being performed by thefirst intercom 104 and, in particular, the electronic controller 410.However, it should be understood that in some embodiments, portions ofthe method 600 may be performed by other devices, including for example,the second intercom 106 and the trunk controller 102. Additionalelectronic controllers may also be included in the first intercom 104that perform all or a portion of the method 600. For ease ofdescription, the method 600 is described in terms of three keypanels andtwo intercoms connected by a single trunk line. However, the method 600may be applied to systems including three or more intercoms, four ormore keypanels, two or more trunk lines, and combinations thereof.

At block 602, the first intercom 104 receives, from the first keypanel114, a call request identifying a remote keypanel coupled to the secondintercom. For example, a user of the first keypanel 114 may activate atoggle switch of the input mechanism 335 to place a call to the thirdkeypanel 118. This input generates a call request control signal to thefirst intercom 104. The call request identifies, among other things, theremote keypanel.

When the first intercom 104 receives a call request, it sets up aconnection (e.g., activating a crosspoint) between the calling keypaneland the called keypanel. The first intercom 104 stores (e.g., in amemory of the electronic controller 410) locations for the keypanels inthe intercom system 100. When a call request is received for a keypanelconnected to another intercom, the first intercom 104 must firstestablish a connection to the other intercom before connecting thecalling keypanel. At block 604, in response to receiving the callrequest from the first keypanel 114 requesting a connection to a remotekeypanel, the first intercom 104 transmits (e.g., via the communicationinterface) a trunk request based on the call request to the trunkcontroller 102 (e.g., using a suitable electronic communicationsprotocol). The call request may include information about the call, forexample, an identifier for the first keypanel, an identifier for theremote keypanel, an identifier for the second intercom 106, and thelike.

The trunk controller 102 receives the call request, and selects (e.g.,from a table containing the trunk definitions 225 stored in the memory210) one or more trunks and/or intervening intercoms that can establisha trunk connection between the first intercom 104 and the intercom towhich the remote keypanel is connected (in this example, the secondintercom 106). The trunk controller 102 generates trunk setup messagesthat include the information needed by the intercoms to setup the trunkand transmits the trunk messages to their respective intercoms.

At block 606, the first intercom 104 receives, from the trunk controller(e.g., via the communication interface), the trunk setup message. Forexample, the trunk message may indicate that the first intercom 104should connect the first port coupled to the first keypanel 114 to asecond port coupled to a trunk line (e.g., connecting input port 1 tooutput port 2 as illustrated in FIG. 5).

As noted, the ports of an intercom are arranged such that any port maybe patched to any other port or ports. At block 608, the first intercom104 activates a first crosspoint (e.g., crosspoint 510 in FIG. 5) basedon the trunk setup message. The first crosspoint is associated with thefirst port and the second port, and activating it (e.g., by actuating anelectronic relay, triggering a solid-state switch, or effecting adigital connection) patches the ports so that audio signals can flowbetween them. Similarly, the second intercom 106 receives a trunk setupmessage indicating that the second intercom 106 should connect the portcoupled to the third keypanel 118 to another port coupled to the sametrunk line (e.g., connecting input port 4 to output port 3 asillustrated in FIG. 5). When both intercoms patch the trunk line totheir respective keypanels a trunk is established between the twokeypanels. In some embodiments, the first intercom 104, the secondintercom 106, the trunk controller 102, or a combination of theforegoing, will start a trunk timer and monitor the signals traversingthe trunk. In such embodiments, when the trunk remains inactive for atime period defined by the trunk timer, the trunk is disconnected,freeing the trunk line for use by other users.

As noted, audio gains (volume levels) are applied at the crosspoints. Bydefault, the crosspoint gains are set to 0 dB so that any signalsreceived at a crosspoint are passed through at their existing gainlevel. To allow the remote keypanel user to regulate the relative volumeof mixed audio signals received at the remote keypanel, a trunk gainvalue is applied.

At block 610, the first intercom 104 applies a trunk gain value to thefirst crosspoint based on the remote keypanel. In some embodiments, inresponse to receiving a request to connect the remote keypanel via atrunk, the first intercom 104 retrieves a trunk gain value (e.g., fromthe memory of the electronic controller 410) based on the first keypaneland the remote keypanel. For example, the memory of the electroniccontroller 410 may store a trunk gain value to be applied whenever thefirst keypanel 114 is patched to the remote keypanel (e.g., the thirdkeypanel 118). In some embodiments, the first intercom 104 applies thetrunk gain value to the first crosspoint based on the trunk setupmessage. For example, the trunk setup message may include a trunk gainvalue to be applied when a trunk is established to link the firstkeypanel and the remote keypanel.

When an audio stream is received by the first intercom 104 from thefirst keypanel 114, the first intercom 104 transmits the audio stream tothe second intercom via the second port coupled to the trunk with anaudio gain based on the trunk gain value. For example, if the trunk gainvalue is −3 dB, then the gain for the received audio stream is adjustedby −3 dB at the crosspoint before the audio stream is transmitted overthe trunk. In this way, the remote keypanel will receive the audiostream at the crosspoint gain level, even if the audio stream is mixedwith other audio streams for transmission over the trunk.

Using the method 600, users of remote keypanels (e.g., a user of thethird keypanel 118) are able to adjust the volumes of signals receivedfrom remote sources over trunks. In one example embodiment, the firstintercom 104 receives, from the second intercom 106, a gain adjustmentvalue associated with the first keypanel and the remote keypanel. Forexample, a user of the remote keypanel may activate the input mechanismof the remote keypanel to adjust the volume of the call from the firstkeypanel by +1 dB.

When the first intercom 104 received the gain adjustment value, itapplies an adjusted trunk gain value to the first crosspoint based onthe gain adjustment value. In this example, the adjusted trunk gainvalue is generated by adding 1 dB to the trunk gain value for the firstcrosspoint. The first intercom 104 transmits the audio stream with anaudio gain based on the adjusted trunk gain value. To preserve the gainsetting for future connections of the same keypanels, the first intercom104 stores (e.g., in a memory of the electronic controller 410), theadjusted trunk gain value, an identifier associated with the firstkeypanel, and an identifier associated with the remote keypanel. In someembodiments, the first intercom 104 transmits this information to thetrunk controller 102 for storage.

As noted, in some embodiments, a trunk timer is used. In suchembodiments, responsive to activating the first crosspoint, the firstintercom 104 begins a trunk timer and monitors the trunk audio. When thetrunk timer expires without receiving an audio input from the firstkeypanel or the remote keypanel, the first intercom 104 deactivates thefirst crosspoint, tearing down the trunk. In some embodiments, when thetrunk is re-established for the same two keypanels, the previouslyadjusted volume is applied to the trunk. In such embodiments, the firstintercom 104 receives, from the first keypanel, a second call requestidentifying the remote keypanel. The second call request issubstantially similar to the call request described above. In response,the first intercom 104 transmits to the trunk controller a second trunkrequest based on the second call request. The first intercom 104receives, from the trunk controller, a second trunk setup message andactivates the first crosspoint based on the second trunk setup message,as described above with respect to the first trunk setup message. Thefirst intercom retrieves the adjusted trunk gain value (e.g., from thememory of the electronic controller 410) based on the first keypanel andthe remote keypanel. For example, identifiers for the first keypanel andthe remote keypanel are used to query a lookup table and return anadjusted trunk gain value matched those identifiers. The first intercom104 then applies the adjusted trunk gain value to the first crosspoint.As a result, the re-established trunk transmits audio from the firstkeypanel at the same gain requested by the remote keypanel during theprevious trunked call.

In some configurations, more than one trunk line may be used to connecttwo intercoms. Because the trunk gain values are stored in relation tothe first keypanel and the remote keypanel, in some embodiments, thefirst intercom 104 applies the adjusted trunk gain values to any trunkedconnection between the first keypanel and the remote keypanel,regardless of which trunk line is used to connect the two.

As described above with respect to FIG. 5, some intercoms employ forkingto patch more than one local keypanel to a remote keypanel over the sametrunk line. In some embodiments, gains are adjusted for each keypanel attheir respective crosspoints.

For example, the first intercom 104 receives, from a second keypanelcoupled to a third port of the first intercom 104 (e.g., the secondkeypanel 116 coupled to input port 5, as illustrated in FIG. 5), asecond call request identifying the remote keypanel coupled to thesecond intercom. In response, the first intercom 104 transmits to thetrunk controller a second trunk request based on the second callrequest. The first intercom 104 receives from the trunk controller asecond trunk setup message. The first intercom 104 activates a secondcrosspoint (e.g., the crosspoint 514 illustrated in FIG. 5) based on thesecond trunk setup message. The first intercom 104 applies a secondtrunk gain value to the second crosspoint based on the second keypaneland the remote keypanel. For example, the first intercom 104 mayretrieve the second trunk gain value from the memory of the electroniccontroller 410 using identifiers for the second keypanel and the remotekeypanel, as noted above.

In some embodiments, adjusting audio gains for remote assignments may beperformed in any one or more of the intercoms that make up the trunkedconnection between the keypanels. For example, when adjusting the audiolevel from the first keypanel 114 to the third keypanel 118 asillustrated in FIG. 5, the audio gain can be adjusted in either thefirst intercom 104 or the second intercom 106 (or even in a combinationof them). For example, when the trunk is forked in the first intercom104 (as illustrated in FIG. 5), the audio gain must be adjusted for theappropriate crosspoint in the first intercom 104. Likewise, if the trunkwere forked in the second intercom 106 (not illustrated), the audio gainmust be adjusted for the appropriate crosspoint in the second intercom106. When the trunk is not forked at either end, the gain may beadjusted in either the first intercom 104 or the second intercom 106. Insome embodiments, the trunk controller 102 determines where to adjustthe gain, and sends messages to the affected intercoms. For example, inresponse to a request for a −6 dB gain adjustment, the trunk controller102 may send a message to the first intercom 104 instructing it to applya −6 dB gain at the appropriate local crosspoint. In another example,the trunk controller 102 may send messages to the first intercom 104 andthe second intercom 106 instructing each to apply a −3 dB gain at theirrespective local crosspoints, resulting in an overall requested pathgain of −6 dB.

Because of the size of some intercom systems remote gain adjustmentcapabilities are limited to preserve limited memory resources. FIG. 7illustrates an example graphical user interface element 700. The element700 is generated by the intercom editor 110 to allow users to configure,for example, the first intercom 104 and the second intercom 106. A usermay specify a maximum panel quantity 704 (“Panels with Gains”), whichlimits how many ports in the system are allowed to request remote gainadjustment. A user may also specify a maximum gain per panel quantity706 (“Gains Per Panel”), which limits the number of individual gainvalues that can be specified by an individual keypanel.

In some embodiments, before remote assignment gains can be adjustedusing the method 600, remote gain adjustment must be enabled for theremote keypanel. FIG. 8 illustrates an example graphical user interfaceelement 800. The element 800 is generated by the intercom editor 110 toallow users to configure, for example, the first keypanel 114, thesecond keypanel 116, and the third keypanel 118. Using checkbox 802, auser can enable remote assignment gains on a keypanel. The number ofremote assignment gains are limited, as noted herein with respect toFIG. 7.

When remote assignment gains have been enabled for a keypanel, gains forremote assignments can be adjusted by users. For example, gains can beadjusted for remote assignments just as for local assignments. Forexample, on a KP-5032 keypanel, a user moves the lever key for theassignment left or right to adjust the gain. In another example, theremote assignment gains can be pre-set using software (e.g., AZedit) onthe intercom editor 110.

In some embodiments, intercoms support multiple independent party lines.For example, in digital intercoms, party lines are a resource withoutany specific hardware such as a physical wire. Multiple users(keypanels) all talk and listen to the same party line, and they willall hear each other because the controller closes the necessarycrosspoints. Using party lines, connected keypanels can listen (withouttalking), talk (without listening), or can talk and listensimultaneously. Using embodiments described herein, a keypanel canadjust the level at which it listens to remote party lines.

One or more embodiments have been described and illustrated in theforegoing specification and accompanying drawings. These embodiments arenot limited to the specific details provided herein and may be modifiedin various ways. Furthermore, other embodiments may exist that are notdescribed herein. Also, the functionality described herein as beingperformed by one component may be performed by multiple components in adistributed manner. Likewise, functionality performed by multiplecomponents may be consolidated and performed by a single component.Similarly, a component described as performing particular functionalitymay also perform additional functionality not described herein. Forexample, a device or structure that is “configured” in a certain way isconfigured in at least that way but may also be configured in ways thatare not listed. Furthermore, some embodiments described herein mayinclude one or more electronic processors configured to perform thedescribed functionality by executing instructions stored innon-transitory, computer-readable medium. Similarly, embodimentsdescribed herein may be implemented as non-transitory, computer-readablemedium storing instructions executable by one or more electronicprocessors to perform the described functionality. As used in thepresent application, “non-transitory computer-readable medium” comprisesall computer-readable media but does not consist of a transitory,propagating signal. Accordingly, non-transitory computer-readable mediummay include, for example, a hard disk, a CD-ROM, an optical storagedevice, a magnetic storage device, a ROM (Read Only Memory), a RAM(Random Access Memory), register memory, a processor cache, or anycombination thereof.

In addition, the phraseology and terminology used herein is for thepurpose of description and should not be regarded as limiting. Forexample, the use of “including,” “containing,” “comprising,” “having,”and variations thereof herein is meant to encompass the items listedthereafter and equivalents thereof as well as additional items. Theterms “connected” and “coupled” are used broadly and encompass bothdirect and indirect connecting and coupling. Further, “connected” and“coupled” are not restricted to physical or mechanical connections orcouplings and can include electrical connections or couplings, whetherdirect or indirect. In addition, electronic communications andnotifications may be performed using wired connections, wirelessconnections, or a combination thereof and may be transmitted directly orthrough one or more intermediary devices over various types of networks,communication channels, and connections. The terms “a” and “an” aredefined as one or more unless explicitly stated otherwise herein. Theterms “substantially,” “essentially,” “approximately,” “about,” or anyother version thereof, are defined as being close to as understood byone of ordinary skill in the art, and in one non-limiting embodiment theterm is defined to be within 10%, in another embodiment within 5%, inanother embodiment within 1% and in another embodiment within 0.5%.Moreover, relational terms such as first and second, top and bottom, andthe like may be used herein solely to distinguish one entity or actionfrom another entity or action without necessarily requiring or implyingany actual such relationship or order between such entities or actions.

Various features and advantages of some embodiments are set forth in thefollowing claims.

What is claimed is:
 1. An intercom device comprising: a plurality ofaudio ports including a first port coupled to a first keypanel and asecond port coupled to a trunk line providing a two-way audio connectionbetween the intercom device and a second intercom device; a plurality ofcrosspoints for interconnecting the plurality of audio ports; acommunication interface; and an electronic processor coupled to theplurality of crosspoints and the communication interface; wherein theelectronic processor is configured to receive, from the first keypanel,a call request identifying a remote keypanel coupled to the secondintercom device; transmit, to a trunk controller via the communicationinterface, a trunk request based on the call request; receive, from thetrunk controller via the communication interface, a trunk setup message;activate a first crosspoint of the plurality of crosspoints based on thetrunk setup message, the first crosspoint associated with the first portand the second port; apply a trunk gain value to the first crosspointbased on the remote keypanel; transmit, with an audio gain based on thetrunk gain value, an audio stream received from the first keypanel tothe second intercom device via the second port; receive, from the secondintercom device, a gain adjustment value associated with the firstkeypanel and the remote keypanel; and apply an adjusted trunk gain valueto the first crosspoint based on the gain adjustment value.
 2. Theintercom device of claim 1, wherein the electronic processor is furtherconfigured to apply the trunk gain value to the first crosspoint basedon the trunk setup message.
 3. The intercom device of claim 1, furthercomprising: a memory; wherein the electronic processor is coupled to thememory and configured to retrieve the trunk gain value from the memorybased on the first keypanel and the remote keypanel.
 4. The intercomdevice of claim 1, wherein the electronic processor is furtherconfigured to transmit the audio stream with an audio gain based on theadjusted trunk gain value.
 5. The intercom device of claim 1, furthercomprising: a memory; wherein the electronic processor is coupled to thememory and configured to store, in the memory, the adjusted trunk gainvalue, an identifier associated with the first keypanel, and anidentifier associated with the remote keypanel.
 6. The intercom deviceof claim 5, wherein the electronic processor is further configured to:responsive to activating the first crosspoint, begin a trunk timer; andwhen the trunk timer expires without receiving an audio input from thefirst keypanel: deactivate the first crosspoint; receive, from the firstkeypanel, a second call request identifying the remote keypanel;transmit, to the trunk controller via the communication interface, asecond trunk request based on the second call request; receive, from thetrunk controller via the communication interface, a second trunk setupmessage; activate the first crosspoint based on the second trunk setupmessage; retrieve the adjusted trunk gain value from the memory based onthe first keypanel and the remote keypanel; and apply the adjusted trunkgain value to the first crosspoint.
 7. The intercom device of claim 1,wherein the plurality of audio ports includes a third port coupled to asecond keypanel; and the electronic processor is further configured toreceive, from the second keypanel, a second call request identifying theremote keypanel coupled to the second intercom device; transmit, to thetrunk controller via the communication interface, a second trunk requestbased on the second call request; receive, from the trunk controller viathe communication interface, a second trunk setup message; activate asecond crosspoint of the plurality of crosspoints based on the secondtrunk setup message, the second crosspoint associated with the secondport and the third port; and apply a second trunk gain value to thesecond crosspoint based on the second keypanel and the remote keypanel.8. The intercom device of claim 7, further comprising: a memory; whereinthe electronic processor is coupled to the memory and configured toretrieve the second trunk gain value from the memory based on the secondkeypanel and the remote keypanel.
 9. The intercom device of claim 7,wherein the electronic processor is further configured to: receive, fromthe second intercom, a second gain adjustment value associated with thefirst keypanel and the remote keypanel; apply a second adjusted trunkgain value to the second crosspoint based on the second gain adjustmentvalue; and transmit to the second intercom device via the second port anaudio stream received from the first keypanel mixed with a second audiostream received from the second keypanel; wherein the audio stream hasan audio gain based on the adjusted trunk gain value and the secondaudio stream has a second audio gain based on the second adjusted trunkgain value.
 10. The intercom device of claim 1, further comprising: amemory; wherein the plurality of audio ports includes a third portcoupled to a second keypanel and a fourth port coupled to a second trunkline providing a second two-way audio connection between the intercomdevice and the second intercom device; and the electronic processor iscoupled to the memory and further configured to receive, from the secondkeypanel, a second call request identifying the remote keypanel coupledto the second intercom device; transmit, to the trunk controller via thecommunication interface, a second trunk request based on the second callrequest; receive, from the trunk controller via the communicationinterface, a second trunk setup message; activate a second crosspoint ofthe plurality of crosspoints based on the second trunk setup message,the second crosspoint associated with the third port and the fourthport; retrieve a second trunk gain value from the memory based on thesecond keypanel and the remote keypanel; and apply the second trunk gainvalue to the second crosspoint.
 11. A method for operating an intercomsystem, the method comprising: receiving, from a first keypanel coupledto a first intercom device, a call request identifying a remote keypanelcoupled to a second intercom device; transmitting, to a trunkcontroller, a trunk request based on the call request; receiving, fromthe trunk controller, a trunk setup message; activating a firstcrosspoint of a plurality of crosspoints based on the trunk setupmessage, the first crosspoint coupled to a first port coupled to a firstkeypanel and a second port coupled to a trunk line providing a two-wayaudio connection between the first intercom device and the secondintercom device; applying a trunk gain value to the first crosspointbased on the remote keypanel; transmitting, with an audio gain based onthe trunk gain value, an audio stream received from the first keypanelto the second intercom device via the second port; receiving, from thesecond intercom, a gain adjustment value associated with the firstkeypanel and the remote keypanel; and applying an adjusted trunk gainvalue to the first crosspoint based on the gain adjustment value. 12.The method of claim 11, wherein applying the trunk gain value to thefirst crosspoint includes applying the trunk gain value based on thetrunk setup message.
 13. The method of claim 11, further comprising:retrieving the trunk gain value from a memory based on the firstkeypanel and the remote keypanel.
 14. The method of claim 11, furthercomprising: transmitting the audio stream with an audio gain based onthe adjusted trunk gain value.
 15. The method of claim 11, furthercomprising: storing in a memory the adjusted trunk gain value, anidentifier associated with the first keypanel, and an identifierassociated with the remote keypanel.
 16. The method of claim 15, furthercomprising: responsive to activating the first crosspoint, beginning atrunk timer; and when the trunk timer expires without receiving an audioinput from the first keypanel: deactivating the first crosspoint;receiving, from the first keypanel, a second call request identifyingthe remote keypanel; transmitting to the trunk controller a second trunkrequest based on the second call request; receiving, from the trunkcontroller, a second trunk setup message; activating the firstcrosspoint based on the second trunk setup message; retrieving theadjusted trunk gain value from the memory based on the first keypaneland the remote keypanel; and applying the adjusted trunk gain value tothe first crosspoint.
 17. The method of claim 11, further comprising:receiving, from a second keypanel coupled to a third port, a second callrequest identifying the remote keypanel coupled to the second intercomdevice; transmitting, to the trunk controller, a second trunk requestbased on the second call request; receiving, from the trunk controller,a second trunk setup message; activating a second crosspoint of theplurality of crosspoints based on the second trunk setup message, thesecond crosspoint associated with the second port and the third port;and applying a second trunk gain value to the second crosspoint based onthe second keypanel and the remote keypanel.
 18. The method of claim 17,further comprising: retrieving the second trunk gain value from thememory based on the second keypanel and the remote keypanel.
 19. Themethod of claim 17, further comprising: receiving, from the secondintercom, a second gain adjustment value associated with the firstkeypanel and the remote keypanel; applying a second adjusted trunk gainvalue to the second crosspoint based on the second gain adjustmentvalue; and transmitting to the second intercom device via the secondport an audio stream received from the first keypanel mixed with asecond audio stream received from the second keypanel; wherein the audiostream has an audio gain based on the adjusted trunk gain value and thesecond audio stream has a second audio gain based on the second adjustedtrunk gain value.